i needed help on this one too. But this is what i got outta the forums.


RBLove wrote on Today 04:52 PM:
Yeah No problem.

19turn actually take a bigger gear than stock. Tire size has everything to do with it. I assume this person is running on carpet?

Tire size x pie (3.14) = ______
Spur / pinion x internal gear ratio = ______

Divide the top number over the bottom and you have roll out. Do not flip these two when dividing..

Example: X-Ray FK with 2.25 in tires ( I do not use mm).

2.25 x 3.14 = 7.06
132sp / 35pin x 1.77 internal = 6.67

7.06 / 6.67 = 1.058 roll out

Depending on track size, but like Cleveland or Snowbords a monster stock would be geared around a 1.00 or little lower. 19t would be at a 1.12 or even higher.

Hope this helps......
Rob